“Maria has suspected this for a long time and she asked the housekeeper,” a source close to the situation told us. “The housekeeper admitted it.

“Maria then went to Arnold and he confessed.” He didn’t volunteer the information, and it could have remained a secret if Maria hadn’t asked.

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Mildred, also known as Patty, couldn’t carry the secret any more according to another source.

“It’s amazing she didn’t crack before this,” said the source.

And Patty was NOT fired by Arnold, says another source, despite earlier reports.

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“Yes, her employment ended, but it ended without animosity,” one source said.

But a friend told RadarOnlne.com: “She was upset with Arnold at the time and didn’t know what to do, she thought about going public, but it was a fleeting thought. Ultimately she didn’t want to hurt Arnold. But she also didn’t want her employment to end.